香港赛马会员总公司
傾聽各國草根真實聲音,縱論全球平民眼中世界
龍騰網首頁 -> 國外新鮮事 -> 正文 Tips:使用 ← → 鍵即可快速瀏覽其他文章
什么時候死亡才是真正的死亡?對豬大腦的研究進一步證明,死亡是一個巨大的灰色區域
2019-05-02 土撥鼠之日 282 0 0  

When is dead really dead? Study on pig brains reinforces that death is a vast gray area

什么時候死亡才是真正的死亡?對豬大腦的研究進一步證明,死亡是一個巨大的灰色區域



For the longest time, “death” used to be when the heart stopped beating and breathing stopped. Then, machines were invented in the 1930s that enabled people to receive air even if they could not take in the air themselves. In the 1950s, machines were developed to help sustain heartbeat.

在很長一段時間里,“死亡”通常用在心臟停止跳動和呼吸停止的時候。然后,20世紀30年代發明了機器,給不能自己吸入空氣的人們傳輸空氣。在20世紀50年代,幫助維持心跳的機器又被開發出來。

But no machine could bring back an irreversibly brain-damaged patient to have a functioning brain. As a result, the concept of “brain death” was introduced as an additional definition of death to complement death by heart-lung failure.

但沒有任何機器能夠讓一個不可逆的腦損傷患者恢復正常的大腦功能。因此,“腦死亡”的概念作為對死亡的補充定義而被引入,以補充心肺功能衰竭所定義的死亡。

The concept of brain death, while legally adopted in the U.S. and in large parts of the world, has remained an area of ongoing discussion. It often centers on how someone can be dead when the heart is beating and the body is warm, even if this function is entirely reached through artificial support. Brain death also is more difficult to conceptualize, as it is a less visible form of death. And isn’t it so much easier to believe what we can see?

腦死亡的概念雖然在美國和世界大部分地區已經得到了合法采用,但仍是一個在持續討論的領域。這個討論的重點通常是一個人如何在心臟正常跳動,身體溫暖的時候死去,即使這個體征完全是通過人工輔助實現的。腦死亡也很難概念化,因為它是一種不太可視化的死亡形式。相信我們所看到的要容易得多。

On April 17, 2019, a study published in Nature that showed signs of activity in pig brains after they were killed added more fuel to the discussion. I am a neurologist specializing in neurocritical care, with both clinical and research interests in acute brain damage, and broad exposure to catastrophic brain injury and brain death. My analysis of the study is that it reinforces much of what we already know, that death is a continuum.

2019年4月17日,發表在《自然》雜志上的一項研究又刺激了這一討論。該研究顯示,死后,豬的大腦出現了活動跡象。我是一名神經危重癥的專科醫師,對急性腦損傷的臨床和研究都有興趣,并廣泛接觸災難性腦損傷和腦死亡。我對這項研究的分析是,它更加強調了我們已經知道的一件事——死亡是一個連續的過程。

When pigs die, can their brains be revived?
小標題: (豬死了之后,它們的大腦能復活嗎?)

In the study, scientists took brains from pigs that had been slaughtered at USDA-regulated facilities, connected them to a machine that pumped an artificial blood-like nutritional fluid through the brains four hours after their “death,” and measured activity of brain cells. They found that even hours after death, blood circulation – or circulation of the artificial blood – and certain brain cell functions could be restored in this experimental setting.

在這項研究中,科學家們從在美國農業部監管的屠宰場中屠宰的豬身上提取了大腦,將它們與一臺機器連接起來,在它們“死亡”四小時后,機器將一種類似血液的人工營養液注入它們的大腦,并測量了腦細胞的活動。他們發現,即使在死亡數小時后,血液循環——或者說人造血液的循環——和某些腦細胞功能也可以在這個實驗環境中恢復。

The conclusion was that demise in the brain after the heart stops beating follows an extended process rather than occurring at a defined moment in time, and that perhaps our brains have a better capacity to heal than is currently known.
Is this news? Yes, on a scientific level – that is, under the microscope, because an experiment like this has not been done before. But, have we not known for a long time that death does not occur within the blink of an eye?

結論是,心臟停止跳動后,大腦的死亡是一個過程,而不是在某個特定的時間點發生,而且我們大腦的愈合能力可能比目前所認為的更好。
這是新聞嗎?在科學的層面上(即在顯微鏡下)是,因為這樣的實驗以前從未做過。但是,難道我們一直不知道死亡并非發生在轉眼之間嗎?

Historic accounts of decapitated bodies vividly describe decapitated bodies taking a few steps or even running.
That means that such a body was not immediately dead. And, conceivably, if one hooked up such a body to blood supply and healed the wounds, most people could likely imagine that it could continue to be maintained with living body parts or cells.

歷史記錄中生動地描述了被斬首的身體走幾步甚至跑幾步的現象。
這意味著這個身體并沒有立即死亡。而且,如果把這個身體與血液供應連接起來,并治愈了傷口,大多數人可能會想象,它可以繼續憑活著的身體器官和細胞來維持生命。

Can a head still be alive after decapitation?
小標題: (斬首后的頭還能活著嗎?)

Even worse to imagine: Could the decapitated head still be conscious for a bit? Perhaps yes.
After the heart stops beating, we consider that someone has died. But, after the heartbeat stops, we also know that sometimes, the heartbeat can come back by itself. This is called autoresuscitation. In this case, someone that appeared dead for a few minutes may not have actually died.

想象一下: 這個被斬掉的腦袋還能清醒一會兒嗎?也許可以。
當一個人的心臟停止跳動后,我們認為他死了。但是我們也知道,在停止之后,心跳有時候可以自己恢復。這叫做自動心肺復蘇。在這種情況下,看上去已經死了幾分鐘的人可能實際上并沒有死。

But the situation is different for the brain than for the heart. When there is a lack of blood flow in the absence of a heart that pumps it, or when there is intrinsic brain injury and blood cannot get in, the situation is tricky. Brains are very sensitive to being deprived of oxygen and energy supply, and various degrees of brain injury occur. Depending on how long the energy fuel to the brain is absent, brain function can remain alive to various degrees and be rekindled to a degree we neuroscientists do not yet fully know. We know that brain function is seriously disturbed, with variable permanence of function loss depending on how long the brain has not had energy.

但是大腦和心臟的情況不同。當沒有心臟泵血,血液無法流動時,或者當有內在的腦損傷,血液無法進入時,情況就很棘手了。大腦對缺氧和缺少能量供應非常敏感,這會導致不同程度的腦損傷。根據大腦缺少能量供應的時間長短,大腦功能可以在不同程度上得以保持,并可以在某種程度上(具體的程度我們神經學家還不完全清楚)被重新激活。我們知道,大腦功能受到嚴重干擾,功能喪失的持續時間取決于大腦缺少能量的時間長短。

The end result of how functional such a damaged brain will come out is one of the biggest challenges we have to learn more about.
After an injury, a whole sequence of consecutive processes occurs that is called secondary brain injury and is triggered by the insult to the brain in the first place. And these processes often cause tremendous damage, and sometimes more than the actual first injury.

大腦受損后的功能如何,是我們需要去了解的最大挑戰之一。
大腦受傷后,一系列連續的過程發生,這被稱為繼發性腦損傷。這一過程通常會造成巨大的傷害,有時甚至比第一次傷害還要嚴重。

For example, a hard blow to the head can result in a bruise or bleeding in the brain, which can be removed by surgery in certain cases. Despite the bleeding being stopped or removed, however, the surrounding brain will sometimes start swelling and bruising even more over the subsequent days, like a big bruise on the thigh goes through stages and color changes. There is not yet a preventive therapy for this, but we know that some factors can make this process worse, such as blood pressure that is too low or lack of oxygen to the brain during the healing phase.

例如,頭部受到重擊可能導致腦部瘀傷或出血,在某些情況下瘀傷可以通過手術移除。然而,盡管停止出血,但在接下來的幾天里,周圍的大腦有時會開始腫脹和瘀傷,甚至會更嚴重,就像大腿上的大瘀傷會經歷不同階段,顏色也會發生變化。目前還沒有針對這種情況的預防方法,但我們知道,一些因素(比如血壓過低,或者在康復階段大腦缺氧)會使這一過程的后果變得更嚴重。

Imagine a broken bone: The cast is just the first step, and there is swelling, pain and weakness for weeks to come. In the brain, the process is more granular. And in neuroscience, we are just now beginning to understand this cascade of events.

想象一下骨折的情況:石膏只是第一步,接下來的幾周會有腫脹、疼痛和虛弱。在大腦中,這個過程會更加細化。我們神經科學現在才剛剛開始了解這一連串的過程。

What to learn from the pig study
小標題: (從對豬的研究中學到什么)

The study of revived pig brain cells does not even come close to touching on this much bigger picture. It is limited to showing that the time span and spectrum of nerve cell function that can persist and at least partially be restored is longer than had been shown so far. Hence, it supports the idea that dying is a process, and puts an additional piece of data on the length of this process.

對再生的豬腦細胞的研究甚至都沒有觸及到更深層次的東西。它僅僅表明了神經細胞的功能可以在更廣的時間跨度下保持并至少部分恢復。因此,它支持了死亡是一個過程的觀點,并增加了這個過程的長度。

But it does not show that these brain cells were able to function as a nerve cell network leading to higher brain function such as consciousness or awareness – the features that set us apart as humans. It also just looks at the immediate restoring of cell function, and not at how these brains do days out, when the continuing processes of secondary brain damage set in.

但這并不表明這些腦細胞能夠像神經細胞網絡一樣運作,神經網絡細胞能夠產生更高的大腦功能,如認知和意識——這些特征使我們人類有別于其他生物。這個實驗也只是觀察腦細胞功能的立即恢復,而不是觀察這些大腦在繼發性腦損傷開始時是如何工作的。

To summarize, in the absence of blood flow, the brain, including all its individual cells will die – eventually. And this study has perhaps expanded the understanding of “eventually.”
Death is a process, and not a moment in time. It is the human desire to put things in categories of black and white, and to have definitions that let us operate in daily life. Death – this is becoming more and more clear – is a large gray zone, and we will have to expect that this gray zone grows as science progresses.

總而言之,在沒有血液流動的情況下,大腦,包括它所有的細胞,最終都會死亡。這項研究也許擴展了對“最終”的理解。
死亡是一個過程,而不是一個瞬間。人類希望把事物按非黑即白的方式分類,并給出一個確切的定義。而死亡是一個巨大的灰色地帶,這一點變得越來越明顯,我們期待這個灰色地帶會隨著科學的進步而變得更明了。

(評論部分)

robin wallace
This sheds new light on the South American culture that keeps their dead around the house for months, and continues to clothe and “feed” them once moved to the crypt.

這讓人們對南美文化有了新的認識——在南美文化中人們讓死者在家里呆上幾個月,并在把他們搬到地窖后繼續給他們穿衣和“喂食”。

On another note, do you really think awareness and consciousness set us apart as humans? I would think as a neuroscientist, you’d be more likely to suggest that those two conditions are also a gray zone, or continuum, where some animals are more and some are less. Especially since you can’t point to a structure in a human brain that awareness and consciousness reside in that animal brains don’t have. And in that light, the pig slaughterhouse is even more ghastly and cruel a place than I thought. I wish scientists like you would advocate for kinder practices, such as no high speed slaughter.

另一方面,你真的認為認知和意識把我們人類跟其他生物分開了嗎?我認為,作為一名神經學家,你更應該說這兩個東西也是灰色地帶,有些動物多一些,有些動物少一些。尤其是當你沒法指出人類大腦中認知和意識所在的哪個區域是動物大腦中所沒有的。從這個角度來看,屠宰場比我想象的還要可怕和殘忍。我希望像你這樣的科學家能提倡更仁慈的做法,比如禁止高速屠宰。

Sharwan kumar
Thanks for your views.
Katharina BuslAssociate Professor, Neurology. Chief, Division of Neurocritical Care, Department of Neurology, University of FloridaIn reply to robin wallace Refers to living versus dead humans. not humans versus animals.

謝謝你的意見。
佛羅里達大學神經內科神經重癥醫學部主任,神經學副教授凱瑟琳娜·巴斯,與羅賓·華萊士討論過關于活人與死人的問題,不是人和動物的問題。

There is no point in answering around the question. All animals whether pigs or humans are animals and are equivalent- neither being inferior or superior. All animals have feelings, pigs may not speak and cry in the language of human beings when decapitated by the animals who call themselves humans. What if Katharine Busls were decapitated for carrying out the type of experiments you describe and comment herein and robin wallace were to comment upon that the way he has done? I am hopeful that you would appreciate that as a true student of neuroscience.Now as for the inferences from the experiments done on the pigs are concerned, that does not make any difference to humans. Moreover, experiments that too in large numbers are needed to be done on human animals rather than on animals other than humans. Best wishes and regards.

回避這個問題是沒有意義的。所有的動物,無論是豬還是人,只要是動物,就都是平等的——沒有優劣之分。所有動物都有感情,豬被自稱為人類的動物斬首時,可能不會用人類的語言訴說和哭泣。如果凱瑟琳·巴斯因為做了你在這里描述和評論的實驗或是羅賓·華萊士因為像原來一樣評論而被斬首的話,又會怎么樣呢?你應該慶幸自己是一名真正的神經科學學生。現在,在豬身上做的實驗中得出的推論,對人類沒有任何意義。應該在人類身上進行大量的實驗,而不是在其他動物身上進行。致以最誠摯的祝愿和問候。

Hugo Pottisch
Studies on pigs show that scientist lack basic empathy and would hence not gain much quality of living if they did live longer.

對豬的研究表明,科學家缺乏基本的同理心,因此,即使他們活得更長,也沒法有效提高生活質量。

——————分割線——————

Paul Smith(樓主)
Perhaps they can do something for the democrats. They appear to be brain dead.

也許他們能為民主黨做些什么。他們似乎是腦死亡患者。

Joe Dirk(回復樓主)
If you cannot make a meaningful contribution to the conversation please refrain from commenting.This site is for academic learning, not quips and slander.

如果你不能對交談做出有意義的貢獻,請不要發表評論。這個網站是為了學術學習,而不是俏皮話和誹謗。
 
香港赛马会员总公司 时时彩小概率稳赚 奥客网七星彩定胆杀号 香港小霸王永久或名 快乐时时官网 特区彩票论坛七星彩开奖结果结果 千里马计划官网最新版本 双色球开奖 重庆时时彩后三包胆是什么意思 时时彩哪种玩法稳赚不 重庆时时彩直播软件